Foam respiratory mask

ABSTRACT

A patient interface for delivering breathable gas to a patient includes a foam interfacing portion adapted to provide a nasal interface to contact under and around the patient&#39;s nose in use and including an orifice adapted to surround both the patient&#39;s nares in use, and a positioning and stabilizing structure to support the foam interfacing portion in an operative position on the patient&#39;s face. The positioning and stabilizing structure is structured to provide a range of rotational, axial, and/or lateral movement to the foam interfacing portion while maintaining a sufficient interface and resisting the application of tube drag and/or headgear tension to the foam interfacing portion.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Australian ProvisionalApplication No. AU 2008901057, filed Mar. 4, 2008, which is incorporatedherein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to a respiratory mask used for treatment,e.g., of Sleep Disordered Breathing (SDB) with Continuous PositiveAirway Pressure (CPAP) or Non-Invasive Positive Pressure Ventilation(NIPPV). In particular, the present invention relates to a respiratorymask with a foam contacting portion. Also, the present invention relatesto a respiratory mask that is comfortable, easy to use and requireslittle maintenance.

BACKGROUND OF THE INVENTION

Typically, respiratory therapy is delivered in the form of a respiratorymask or mask system positioned between a patient and apparatus providinga supply of pressurized air or breathing gas. Mask systems in the fieldof the invention differ from mask systems used in other applicationssuch as aviation and safety in particular because of their emphasis oncomfort. This high level of comfort is desired because patients mustsleep wearing the masks for hours, possibly every night for the rest oftheir lives. In addition, therapy compliance can be improved if thepatient's bed partner is not adversely affected by the patient's therapyand wearing of the mask generally.

Mask systems typically have a highly clinical aesthetic (as will bedescribed below). This may lead to patients becoming embarrassed abouttheir therapy since the clinical aesthetic serves as a blatant reminderthat they are ill and consequently can leave a negative perception ofthe patient in the mind of an observer.

Mask systems typically, although not always, comprise (i) a rigid orsemi-rigid portion often referred to as a shell or frame, (ii) a soft,patient contacting portion often referred to as a cushion, and (iii)some form of headgear to hold the frame and cushion in position. If themask system does include multiple components, at least some assembly andadjustment may be required, which can be difficult for patients who maysuffer from lack of dexterity, etc. Further, mask systems often includea mechanism for connecting an air delivery conduit. The air deliveryconduit may preferably be connected to a blower or flow generator.

Patient contacting portions, e.g., cushions, are typically constructedof a silicone material, but patient contacting portions including foamare known. For example, U.S. Pat. No. 5,429,683 (Le Mitouard) disclosesa lining for a mask made of a polyurethane foam covered with skin (e.g.,latex or silicone). However, skinned foam does not allow the portion incontact with the face to breathe, which can lead to skin irritation, andthe sealing portion may be subject to creasing which may causediscomfort and lead to leak. The skin can also feel too hard for somepatients, depending on the thickness and support structure. The skinalso does not allow a high degree of local deformation and may besubject to tension transfer across its surface, which can result inshifting of the mask on the face and loss of seal/comfort.

A range of mask systems are known including nasal masks, nose & mouthmasks, full face masks and nasal prongs, pillows, nozzles & cannulae.Masks typically cover more of the face than nasal prongs, pillows,nozzles and cannulae.

There is a continuous need in the art to provide mask systems with ahigh level of comfort and usability and a newly perceived need toprovide mask systems having improved aesthetics.

SUMMARY OF THE INVENTION

One aspect of the invention is to provide an attachable interfacingportion for a respiratory mask.

Another aspect of the invention is to provide a removably attachableinterfacing portion for a respiratory mask.

In an embodiment, the respiratory mask is a nasal mask, and theinterfacing portion is a foam contacting portion that is arranged in usebetween the nose of the patient and the mask system. The foam contactingportion provides a seal between the nares of the patient and the masksystem so as to deliver pressurized gas to the patient. The mask systemmay include a cushion, gusset and/or frame.

In one form, the nasal mask system may be provided with a releasable andreplaceable foam contacting portion that it connected to the mask systemby at least one connector.

In embodiments, the foam contacting portion may be connected to the masksystem (e.g., connected to the frame, decoupling element, and/orheadgear) by male and female connectors, a hook and loop arrangement, apress stud arrangement, hook and loop material, a clip arrangement,and/or an adhesive. In another embodiment, the foam contacting portionmay be connected or otherwise provided to the mask system using existingstructure on the frame, decoupling element, and/or headgear, e.g.,without connectors and/or adhesive.

In another form, the nasal mask system may be provided with a removablefoam contacting potion that adjoins to the mask system by wrapping aboutor around the mask system.

In one form, the foam contacting portion may be retrofitted to anexisting nasal mask.

In another form, the foam contacting portion includes a foam sleeve thatthat may be slidingly positioned over a support structure. The foamsleeve may be removably positionable. In one form, the foam sleeve issock-like.

Another aspect of the invention relates to a patient interface fordelivering breathable gas to a patient including a foam interfacingportion adapted to provide a nasal interface to contact under and aroundthe patient's nose in use and including an orifice adapted to surroundboth the patient's nares in use, and a positioning and stabilizingstructure to support the foam interfacing portion in an operativeposition on the patient's face. The positioning and stabilizingstructure is structured to provide a range of rotational, axial, and/orlateral movement to the foam interfacing portion while maintaining asufficient interface and resisting the application of tube drag and/orheadgear tension to the foam interfacing portion.

Other aspects, features, and advantages of this invention will becomeapparent from the following detailed description when taken inconjunction with the accompanying drawings, which are a part of thisdisclosure and which illustrate, by way of example, principles of thisinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings facilitate an understanding of the variousembodiments of this invention. In such drawings:

FIG. 1 depicts a side view of a nasal mask with a foam contactingportion in use according to an embodiment of the present invention;

FIG. 2 depicts a top view of the nasal mask of FIG. 1;

FIG. 3 depicts a front view of the nasal mask of FIG. 1;

FIGS. 4 and 5 depict isometric views of a nasal mask with a foamcontacting portion assembled according to an embodiment of the presentinvention;

FIG. 6 depicts a side view of the nasal mask of FIGS. 4 and 5;

FIG. 7 depicts a front view of the nasal mask of FIGS. 4 and 5;

FIG. 8 depicts a top view of the nasal mask of FIGS. 4 and 5;

FIG. 9 depicts a rear view of the nasal mask of FIGS. 4 and 5;

FIG. 10 depicts a side view of a foam contacting portion according to anembodiment of the present invention;

FIG. 11 depicts a side view of an unassembled foam contacting portionand mask system according to an embodiment of the present invention;

FIG. 12 depicts a side view of an assembled foam contacting portion andmask system according to an embodiment of the present invention;

FIG. 13 depicts front and rear views of an assembled foam contactingportion and mask system in use according to an embodiment of the presentinvention;

FIG. 14 depicts a top view of a foam contacting portion with anintermediate connecting structure according to an embodiment of thepresent invention;

FIGS. 15A, 15B, 15C, and 15D depict top views of foam contactingportions according to embodiments of the present invention;

FIG. 16 depicts an isometric view of a foam contacting portion accordingto an embodiment of the present invention;

FIG. 17 depicts a rear view of the foam contacting portion of FIG. 16;

FIG. 18 depicts a top view of the foam contacting portion of FIG. 16;

FIGS. 19, 20 and 21 depict various views of a foam contacting portionreconnecting to itself about a mask system according to an embodiment ofthe present invention;

FIG. 22 depicts a side view of an unassembled foam contacting portionand mask system with a hook and loop connection according to anembodiment of the present invention;

FIGS. 23 and 24 depict a side view of a hook and loop connection inassembly according to an embodiment of the present invention;

FIG. 25 depicts a rear view of a hook and loop connection in assemblyaccording to an embodiment of the present invention;

FIGS. 26, 27 and 28 depict various views of an assembled foam contactingportion and mask system with a hook and loop connection using headgearconnectors according to an embodiment of the present invention;

FIGS. 29 and 30 depict a side view of an unassembled foam contactingportion and mask system with a hook and loop connection using a detentaccording to an embodiment of the present invention;

FIG. 31 depicts a side view of an unassembled foam contacting portionand mask system with a stud connection according to an embodiment of thepresent invention;

FIG. 32 depicts a front view of an assembled foam contacting portion andmask system with a clipped connection according to an embodiment of thepresent invention;

FIG. 33 depicts a back view of an assembled foam contacting portion andmask system with a clipped connection according to an embodiment of thepresent invention;

FIG. 34 depicts a side view of an assembled foam contacting portion andmask system with a clipped connection according to an embodiment of thepresent invention;

FIG. 35 depicts a top view of an assembled foam contacting portion andmask system with a clipped connection according to an embodiment of thepresent invention;

FIG. 36 depicts a rear view of an assembled foam contacting portion andmask system with a clipped connection according to an embodiment of thepresent invention;

FIG. 37 depicts a front view of a foam contacting portion with a clipconnection according to an embodiment of the present invention;

FIG. 38 depicts a back view of a foam contacting portion with a clipconnection according to an embodiment of the present invention;

FIG. 39 depicts a side view of a foam contacting portion with a clipconnection according to an embodiment of the present invention;

FIG. 40 depicts a top view of a foam contacting portion with a clipconnection according to an embodiment of the present invention;

FIG. 41 depicts a rear view of a foam contacting portion with a clipconnection according to an embodiment of the present invention;

FIGS. 42 and 43 depict the naris region of a patient;

FIG. 44 depicts a top view of a foam contacting portion according to anembodiment of the present invention;

FIG. 45 depicts a side view of the foam contacting portion of FIG. 44;

FIG. 46 depicts a side view of a locking pin according to an embodimentof the present invention;

FIG. 47 depicts a side view of a mask system according to an embodimentof the present invention;

FIG. 48 depicts a side view of a mask system according to an embodimentof the present invention;

FIG. 49 depicts an isometric view of a support structure according to anembodiment of the present invention;

FIG. 50 depicts a bottom view of the support structure of FIG. 49;

FIG. 51 depicts a top view of the support structure of FIG. 49;

FIG. 52 depicts a front view of the support structure of FIG. 49;

FIG. 53 depicts a rear view of the support structure of FIG. 49;

FIG. 54 depicts a side view of the support structure of FIG. 49;

FIG. 55 depicts an isometric view of a mask system according to anembodiment of the present invention;

FIG. 56 depicts a top view of the mask system of FIG. 55;.

FIG. 57 depicts a side view of the mask system of FIG. 55;

FIG. 58 depicts a bottom view of the mask system of FIG. 55; and

FIG. 59 depicts a front view of the mask system of FIG. 55.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

The following description is provided in relation to several embodimentswhich may share common characteristics and features. It is to beunderstood that one or more features of any one embodiment may becombinable with one or more features of the other embodiments. Inaddition, any single feature or combination of features in any of theembodiments may constitute additional embodiments.

In this specification, the word “comprising” is to be understood in its“open” sense, that is, in the sense of “including”, and thus not limitedto its “closed” sense, that is the sense of “consisting only of”. Acorresponding meaning is to be attributed to the corresponding words“comprise”, “comprised” and “comprises” where they appear.

The term “air” will be taken to include breathable gases, for exampleair with supplemental oxygen. It is also acknowledged that the positiveairway pressure (PAP) devices or flow generators described herein may bedesigned to pump fluids other than air.

In broad terms, a patient interface in accordance with an embodiment ofthe invention may comprise three functional aspects: (i) interfacing,(ii) positioning and stabilizing, and (iii) air delivery. These threefunctional aspects may be constructed from one or more structuralcomponents, with a given structural component potentially fulfillingmore than one function. For example, a mask frame may serve as part of apositioning and stabilizing function and allow the supply of air.

In an embodiment, as shown in FIGS. 1-3, the patient interface 10 mayinclude a mask system 100, a positioning and stabilizing structure 30,and an air delivery system 130. Mask system 100 may include aninterfacing portion 200. Positioning and stabilizing structure 30 mayinclude a frame 110 and/or decoupling element 170 and/or a headgear 50(that may include top straps 60, a back strap 70, one or more sidestraps 80 and rigidizers 90). Air delivery system 130 may include: anelbow 140 and a tube 150.

In addition, a patient interface 10 in accordance with an embodiment ofthe invention may perform other functions including venting of exhaledgases, decoupling of potentially seal disruptive forces and adjustmentfor different sized faces. Venting may be performed by differentstructures, e.g., such as the frame 110, the elbow 140 and/or the tube150.

1. Interfacing 1.1 Introduction

In an embodiment, the interfacing function is provided by a nasalcushion (or “nasal cradle”) that is placed at an entrance to thepatient's nares. The nasal cushion is structured to form an interfacewith the nares and is shaped, oriented, sized and constructed so asprovide a fit with a range of differently shaped and located nares.

The nasal cushion may be formed of foam (also referred to as a foamcontacting portion). As shown generally in FIGS. 1-3, nasal cushion orfoam contacting portion 200 may be positioned at the nares or under thenose. Foam contacting portion 200 may cushion the nares of the patientto increase comfort. Foam contacting portion 200 may also seal with thenares of the patient, e.g., if the foam is a closed cell foam.Alternatively, foam contacting portion 200 may be constructed from anopen cell foam or a foam with some open cells, such that it allows acertain degree of leak while delivering sufficient pressure to thepatient in the intended therapeutic effect. Instead, such a foam willallow some air to pass through the foam and leak gases into theatmosphere. This may be desirable to assist in venting.

In an embodiment, the foam contacting portion 200 may be maintained inposition using stabilizing portions or rigidizers 90 attached to, orformed as part of headgear 50. In this form, the mask system 100 may begenerally arranged per ResMed's MIRAGE SWIFT™ nasal pillows and asdescribed in PCT Publication No. WO 2004/073778 (Gunaratnam et al), thecontents of which are hereby expressly incorporated by cross-reference.

1.2 Foam

The foam used for the foam contacting portion 200 may be the same asthat disclosed in PCT Publication No. WO 2008/070929 (Veliss et al),filed 14 Dec. 2007, which is incorporated herein by reference in itsentirety. Alternatively, any suitable foam may be used, for exampleskinned foam.

In another embodiment, the cushion or foam contacting portion 200 of themask system 100 may be the cushion disclosed in U.S. patent applicationSer. No. 12/219,852 (Guney et al), filed 11 Jan. 2008, which isincorporated herein by reference in its entirety.

The foam contacting portion 200 may be a single piece of foam. Inanother form, the foam contacting portion 200 may be multiple pieces offoam joined together by any suitable means, for example gluing or insertmolding.

As shown in the embodiment of FIGS. 4-9, the foam contacting portion 200may have an orifice 250 for delivery of pressurized air. In one form,the orifice 250 provided to the foam contacting portion 200 will alignwith an orifice or aperture 175 or orifices in the decoupling element170 (e.g., see FIGS. 11 and 12) and/or aperture 115 on frame 110 (e.g.,see FIGS. 8 and 9) which is connected to elbow 140 and tube 150, so asto deliver pressurized gas to the patient. The orifice 250 or orificesprovided to the foam contacting portion 200 may be the same size,smaller or larger than the aperture 175 and/or aperture 115.

In an embodiment, the thickness of foam contacting portion 200 may be0.5-50 mm. For example, the thickness of foam contacting portion 200 maybe 7-15 mm. In an exemplary embodiment, the thickness of foam contactingportion 200 may be 11 mm.

In an embodiment, the length of foam contacting portion 200 may be 10mm-200 mm (or its largest length if it is not square). For example, thelength of foam contacting portion 200 may be 40-120 mm. In an exemplaryembodiment, the length of foam contacting portion 200 may be 105 mm. Inan embodiment, the width of foam contacting portion 200 may be 10 mm-100mm (or its largest width if it is not square). For example, the width offoam contacting portion 200 may be 30-70 mm. In an exemplary embodiment,the width of foam contacting portion 200 may be 50 mm.

As disclosed in PCT Publication No. WO 2008/070929 (Veliss et al), thefoam contacting portion may be impermeable or air permeable. Airpermeability may give the foam interface a unique breathability, whichacts to increase the comfort at the interface with the user's nose andskin. All air permeability aspects of PCT Publication No. WO 2008/070929(Veliss et al) are incorporated herein by reference, and all embodimentsin this disclosure may contain foam that is air permeable.

In another embodiment, the foam contacting portion 200 may beretrofitted to existing mask designs, for example ResMed's MIRAGE SWIFT™as disclosed in U.S. Pat. No. 7,318,437 (Gunaratnam et al) and U.S.Patent Publication No. 2005/0241644 (Lynch et al), each of which isincorporated herein by reference.

1.3 Interface Attachment

Desirable features of an attachment mechanism of the foam contactingportion 200 to the positioning and stabilizing structure may include:satisfactory comfort, effective position of the interfacing portionand/or being easy to use. Due to the softness of foam, hard connectingpieces may in some forms be felt by the patient's face through the foam.Thus, attachment mechanisms that avoid such patient contact may bedesired.

In another embodiment, the foam contacting portion 200 may be connectedto a positioning and stabilizing structure such as a frame 110 and/or adecoupling element 170 or any other part of the mask system 100 byconnecting elements such as hook and loop connectors, press studs, etc.Exemplary connecting elements are described below.

1.3.1 Wrap

In an embodiment, as shown in FIG. 4-13, the foam contacting portion 200may be connected to a mask system 100 by wrapping the foam over oraround the mask system 100. The foam contacting portion 200 may besecured in its wrapped position on the mask system 100 by a maleconnector 300 and female connector 310 or series of connectors 300, forexample see FIGS. 9, 10-11, 13, 16 and 17. In the illustratedembodiment, the male connector 300 is provided to the foam contactingportion 200 and the female connector 310 is provided to the frame 110and/or decoupling element 170. However, it should be appreciated thatthe reverse arrangement is possible, i.e., male connector may beprovided to the frame and/or decoupling element and the female connectormay be provided to the foam contacting portion.

The foam contacting portion 200 may be any shape such as generallyrectangular (see FIG. 15A), oval (see FIGS. 15C and 16-18) or hexagonal(see FIG. 15B). Additionally, the foam contacting portion 200 may be anyirregular shape, e.g., Y-shaped (see FIG. 15D).

As shown in FIG. 11, the foam contacting portion 200 may have maleconnectors 300 that engage with opposing female connectors 310 on themask system 100. The female connectors 310 on the mask system 100 may beon a flexible component (for example, decoupling element 170).Alternatively, the female connectors 310 on the mask system 100 may beon a less flexible component (for example, frame 110).

The male connectors 300 may be fixed to the foam contacting portion 200by a range of techniques, for example glue. The female connectors 310may be fixed to the mask system 100 by a range of techniques, forexample glue. In another form, the female connectors 310 may beco-molded to the mask system 100. However, the male and femaleconnectors may be permanently or removably attached in other suitablemanners.

In a further embodiment, the foam contacting portion 200 may not connectto the mask system 100 by male connectors 300 on the foam contactingportion 200 and female connectors 310 on the mask system 100, e.g.,instead the foam contacting portion 200 may reconnect to itself. Forexample, as shown in FIG. 19-21, the male connectors 300 will be placedat one end of the foam contacting portion 200 with the female connectors310 at the other end of the foam contacting portion 200, which can thenbe wrapped around the mask system 100 and connected together atconnection points 320.

In another embodiment, the foam contacting portion may include astretchable foam structured to expand or stretch to fit over the frame,decoupling element, etc., and then return to its original shape totightly grasp the intended surface.

In a further embodiment, the connection mechanism may be via a hook 330and loop 340 system, as shown in FIGS. 22-25. The male connectors 300 onthe foam contacting portion 200 may take the form of hook 330. Thefemale connectors 310 on the mask system 100 may take the form of loop340. The loop 340 may be an additional piece attached to the mask system100 or it may be a hole or aperture in the mask system 100 to allowengagement of the hook 330 (e.g., see FIGS. 23-25).

Alternatively, the reverse arrangement is possible (i.e., loop 340 orhole on the foam contacting portion 200 and hook 330 on the mask system100). In this form, the loop 340 may be a hole in the foam contactingportion 200, and the hook 330 on the mask system 100 may be an attachedor co-molded hook 330 or may be a pre-existing structure on the masksystem 100. For example, FIGS. 26-28 illustrate an embodiment in whichconnectors 350 on the frame 110 (e.g., headgear connecting portions forattaching headgear) extend through respective openings 340 provided toends of the foam contacting portion. In yet another form, the hook 330may have a detent 335 to ensure retention of the loop 340, as shown inFIGS. 29-30. The hook 330 and loop 340 may be made from a range ofdifferent materials or combination of materials, including but notlimited to: wire, silicone, polycarbonate, polypropylene, TPE,polyethylene or any other suitable material.

In a further embodiment, the connection mechanism may be achieved by apress stud 360 as shown in FIG. 31. The male connectors 300 on the foamcontacting portion 200 may take the form of a stud 360. The femaleconnectors 310 on the mask system 100 (e.g., frame 110 or decouplingelement 170) may take the form of a hole or recess 370. Alternatively,the reverse arrangement is possible (i.e., hole 370 on the foamcontacting portion 200 and stud 360 on the mask system 100). The pressstud 360 may be made from materials such as metals, polymers or anyother suitable material.

In a further embodiment, as shown in FIGS. 44-47, the foam contactingportion 200 may be provided with apertures 380 that are intended to bepositioned adjacent alignment holes 180 on the mask system 100. A pin oranchor 390 may be used to secure foam contacting portion 200 onto masksystem 100 by inserting the anchor 390 through apertures 380 andalignment holes 180 (see FIG. 47). Anchor 390 may have one or morelocking portions 395 so that once in position, the foam contactingportion 200 remains in its position on the mask system 100.

In a further embodiment, the foam contacting portion 200 may be wrappedonto or around the mask system 100 and connected by other type ofmechanisms, including but not limited to hook and loop material (e.g.,Velcro™ or magnets.

In a further embodiment, the wrapped foam contacting portion 200 may bepermanently connected to the mask system 100, for example, by gluing,welding or co-molding. For example, the mask system 100 may be made froma foam that can be co-molded with another foam to form the foamcontacting portion 200. In yet another embodiment, the foam may be aflocking foam that is provided to (e.g., sprayed onto) the frame,decoupling element, etc.

Exemplary benefits of the wrapped foam contacting portion 200 mayinclude: the ease of sealing the foam contacting portion with thepatient and the mask system, continuity of feel, top lip comfort,retro-fitability, intuitiveness of assembly and mass productioncapability. Other benefits of the wrapped foam may include: if theintention is to replace the foam contacting portion on a regular basis(e.g., daily, weekly or monthly—as disclosed in PCT Publication WO2008/070929 (Veliss et al)), the portion that is disposed of is smallcompared to the mask system. This embodiment therefore minimizes wasteand maximizes efficiencies around the packaging, storage andtransportation of the replacement foam contacting portions.

1.3.2 Clip

In another form, the foam contacting portion 200 may be connected to amask system 100 by clipping the foam into the mask system 100. The foamcontacting portion 200 may be secured in its clipped position on themask system 100, e.g., by an interference fit.

FIGS. 32-36 show foam contacting portion 200 clipped into the masksystem 100 by a clip 400. Clip 400 is slidably engaged with mask system100 and secures by an interference fit with a portion (e.g., frame 110)of the mask system 100. In an embodiment, clip 400 may be interferencefit via locking bumps 410 with step 120 on mask system 100 (see FIG.48). In an alternative embodiment, clip 400 may be secured in place byanother other means, including but not limited to: screw type mechanism.In another alternative embodiment, the clip 400 may be permanentlysecured to mask system 100, for example, by adhesive. In anotheralternative embodiment, clip 400 may be co-molded or be continuous withthe mask system 100.

The clip 400 may be fixed to the foam contacting portion 200permanently, for example by adhesive or co-molding. Alternatively, clip400 may be releasably connected to foam contacting portion 200,including but not limited to: hook and loop material (e.g., Velcro™).

In an embodiment, clip 400 may have a support structure 420 that mayhave a generally elliptical cross section (e.g., see FIGS. 33, 34,37-39, and 41). Support structure 420 may engage with mask system 100 tosecure the foam contacting portion 200 in place. Support structure 420may also assist in presenting the foam contacting structure 200 at adesirable orientation to the patient's nose. Support structure 420 maybe hollow to allow the flow of pressurized gas from air delivery tube150 to orifice 250 of foam contacting portion 200.

In an embodiment, clip 400 may comprise an upper surface 440 thatengages with foam contacting portion 200 (e.g., see FIGS. 33, 34, 39,and 41). Upper surface 440 may be generally planar. In an exemplaryembodiment, upper surface 440 may be curved to conform to the contoursof the patient's face to improve comfort and seal of the mask. Uppersurface 440 may be as wide as the foam contacting portion 200.Alternatively, upper surface 440 may be smaller or less wide than thefoam contacting portion 200 such that the outer edge of foam contactingportion 200 is able to overhang the upper surface 440 and thus flex atits edge. This arrangement may allow the foam contacting portion tobetter conform to the patient's face.

1.3.3 Other

In a further embodiment, the foam contacting portion 200 need not beconnected to the mask system 100 via connecting elements. Rather, thefoam contacting portion 200 may be placed on the mask system 100 byother means such as pulled over (e.g., like a sock). For example, asshown in FIGS. 55-59, contacting portion 200 may be a cylindrical orcontinuous portion of foam with an opening 800 to receive the frame 110and headgear connecting portions 112. Foam contacting portion 200 mayalso have orifice 250 for interfacing with aperture 175 in decouplingportion 170 to allow the delivery of breathable gas to the patient. Foamcontacting portion 200 may also have opening 260 for interfacing withaperture 115 of frame 110.

In another embodiment, the foam contacting portion 200 may be connectedto an intermediate connecting structure 315 (see FIG. 14). Thisintermediate connecting structure 315 may connect to the foam contactingportion 200 on one side and connect to the mask system 100 on the otherside. This may include but is not limited to: the foam contactingportion 200 may be connected to a piece of flexible fabric material(e.g., Breath-O-Prene™ by Accumed) which is then connected to the masksystem 100 (or part(s) of the mask system 100). Alternatively, theintermediate connecting structure 315 shown in FIG. 14 may not connectto the mask system 100, instead it may wrap around the mask system andthe left and right intermediate connecting structures 315 may connect toeach other.

In a further embodiment, the foam may be fixed (e.g., using an adhesive)to an adaptor or clipping mechanism, which in turn connects via aninterference fit onto the mask frame.

1.4 Interface Size

In a further embodiment, the foam may be provided in various sizes toaccommodate varying anthropometric requirements. Typical nasal pillowdesigns have sizes based on the nostrils of the population as thesepillows seal around the nares. However, the same sizing may not be idealfor the foam contacting portion 200 as it does not seal on the edge of,or inside the nares. Instead sizing may be based on sealing against thearea around the nares (as indicated by the dashed line dl around thenares in FIG. 42).

FIG. 42 presents a two-dimensional view of the underside of the nose anddefines the areas that may be considered for sealing the nostrils. Theorifice 250 on the foam contacting portion 200 should be within thebounds of the area of the nose (shown by the dashed line d2 in FIG. 42)so that the mask can sealingly engage with the nose. Should the orifice250 be any larger than the region of the nose (dashed line d2), the maskmay leak. In an embodiment, the orifice 250 should not be any smallerthan the region within the nares (shown by the dashed line d1) so as toocclude the patient's airway. The orifice in the foam may encroach onthe nostril openings on some noses and some degree of partial occlusionmay be acceptable.

In a further embodiment, there may be one orifice 250 in the foamcontacting portion 200. In one form, the orifice 250 in the foamcontacting portion 200 may be generally trapezoidal or ‘D’ shaped asshown in FIGS. 8, and 16-18. In another form, the orifice 250 may becircular or oval (as shown in FIGS. 14 and 15A-15D), square (not shown)or any other shape fitting within the aforementioned limits.

In a further embodiment and referring to FIG. 43, the orifice 250 in thefoam contacting portion 200 may be 15-50 mm wide (indicated in FIG. 43by dimension 500). In an exemplary embodiment, the orifice 250 in thefoam contacting portion 200 may be about 22 mm wide. In anotherexemplary embodiment, the orifice 250 in the foam contacting portion 200may be about 31 mm wide. In an embodiment, the orifice 250 in the foamcontacting portion 200 may be 5-30 mm high (indicated in FIG. 43 bydimension 600). In an exemplary embodiment, the orifice 250 in the foamcontacting portion 200 may be about 11 mm high. In another exemplaryembodiment, the orifice 250 in the foam contacting portion 200 may beabout 16 mm high.

In a further embodiment, the orifice 250 in the foam contacting portion200 may have an angle of 10-80° (indicated in FIG. 43 by dimension 700).In an exemplary embodiment, angle 700 is about 67° . In anotherexemplary embodiment, angle 700 is about 50° .

In a further embodiment, there may be more than one orifice 250 in thefoam contacting portion 200. In one form, there may be two orifices 250,e.g., each generally oval in shape. In another form, there may be aplurality of orifices 250 (for example, 3, 4, 5, 10 or more), e.g., eachthat are generally round. In another form, there may be multipleorifices 250 of any shape, within the limits shown above (indicated bythe dashed lines d1 and d2 in FIG. 42).

2. Positioning and Stabilizing Structure 2.1 Introduction

A patient interface 10 provides a structure for suitable positioning,suspension and stabilizing of the interfacing portion 200 of the patientinterface 10 at an entrance to the airways of the patient. Thisstructure includes: the decoupling element 170, the frame 110 andheadgear 50 with rigidizers 90. The decoupling element 170 acts as aform of suspension system or force insulation system whereby it isolatesforces from one portion of the patient interface 10 from another portionof the patient interface 10. The headgear 50 and rigidizers 90 form astructure that may resist bending in one or more directions (and/or fromtube drag) and yet is flexible to conform to different facialgeometries, or to move in response to other potentially disruptiveforces. In combination with the suspension system, a greater range ofmovement of a mask system in accordance with an embodiment of theinvention can be accommodated without disrupting the seal than in priorart mask systems.

2.2 Frame

A frame 110 in accordance with an embodiment of the present invention asshown in FIGS. 49-54, serves a number of functions, including: aconnection point to decoupling element 170, headgear rigidizers 90 andelbow 140. A given functional feature may reside in differentstructures. For example, the stabilizing portion of headgear 50 may beformed as part of a frame 110 either additionally or alternatively.

Frame 110 may connect to the elbow 140 via aperture 115, whereby theelbow clips into the aperture 115, or interfaces with the aperture 115by any such means so as to join the elbow 140 to the frame 110. Frame110 may be generally rectangular or any other desired shape, for examplesee FIGS. 49-54. Frame 110 is intended to support the decoupling element170 and foam contacting portion 200 and connect the mask system 100 tothe headgear 50, thereby securing the mask system 100 on the patient'sface. Frame 110 connects to the headgear 50 by connecting portions 112,where rigidizers 90 removably connect to connecting portions 112 (e.g.,see FIG. 7). Such a connection is described in U.S. patent applicationSer. No. 12/219,852 (Guney), which is incorporated herein by referencein its entirety. Frame 110 may be at least partially constructed from aresilient material such as silicone, polycarbonate, polypropylene,nylon, or any other desired material.

2.3 Decoupling Element

Decoupling element 170 may be generally oval as shown in FIGS. 11 and49-54 with orifice 175 adapted to align with opening in foam contactingportion 200. Decoupling element 170 may absorb some of the forces fromthe frame, headgear and tube by flexing and compressing (e.g., like agusset or suspension system) so as to prevent misalignment of the foamcontacting portion 200 with the nares of the patient. Decoupling element170 may be formed from a flexible material such as silicone. Decouplingelement 170 may be connected to frame 110 by an interference fit.Alternatively, decoupling element 170 may be permanently fixed or formedwith the frame 110 by co-molding or glue. Decoupling element 170 mayalso be attached to the foam contacting portion. In one form, the foamcontacting portion 200 is a layer of foam that is wrapped, connected,slid or otherwise positioned on a supporting structure.

In a further embodiment, the decoupling element 170 of the supportstructure may be the decoupling element disclosed in U.S. patentapplication Ser. No. 12/219,852 (Guney), which is incorporated herein byreference in its entirety. In an embodiment, the frame 110 of the masksystem 100 may be the frame disclosed in U.S. patent application Ser.No. 12/219,852 (Guney).

The particularly soft mechanical properties of an exemplary foam (asdisclosed in PCT Publication No. WO 2008/070929 (Veliss et al)) meansthat the foam contacting portion may be provided with support andreinforcement to perform its function with the nasal air passages. Theframe 110 and decoupling element 170 may be suitable structures toprovide this supporting mechanism, providing appropriate balance betweenshape and support for positioning the foam contacting portion 200,structural compliance and resilience for comfort on the nose (e.g.,allow rotational, axial, and/or lateral movement to resist tube drag andheadgear tension).

2.4 Headgear

Headgear 50 may include three main strap sections: top straps 60, backstrap 70 and side straps 80. Top straps 60 may be placed over the top ofthe patient's head and may be one continuous piece of material ormultiple pieces of material joined together by a buckle 95 as shown inFIGS. 1-3.

Back strap 70 may be placed around the back of the patient's head andmay be one piece of continuous material or multiple pieces of materialjoined together by a buckle.

Top strap 60 and back strap 70 may be adjusted using hook and loopfasteners (such as Velcro™) or with the buckle 95. Buckle 95 may alsohave a lock that prevents the top strap 60 from loosening off. Such abuckle 95 with lock is described in U.S. Pat. No. 7,318,437 (Gunaratnamet al), which is incorporate herein by reference in its entirety.

Side straps 80 are generally positioned on the sides of the patient'sface, from above or near the ear, passing under the eyes and ending atthe nose of the patient. Side straps 80 may be reinforced withrigidizers 90 that may assist in supporting the mask system 100 inposition. Rigidizers 90 may be attached to side straps at: the patientcontacting side of side straps 80 (not shown), within side straps 80 byco-molding or other such technique (not shown), or on the exteriornon-patient contacting side of side straps 80 (see FIGS. 1 and 3).Rigidizers 90 may be connected to side straps 80 by: gluing, stitching,co-molding, or any other suitable means.

Side straps 80 may also include cheek supports 85 that lie generallyhorizontally on the cheeks of the patient, generally at the cheek boneregion, to better position the mask system 100 on the face of the user.Such an arrangement is shown in U.S. patent application Ser. No.12/219,852 (Guney).

3. Air Delivery 3.1 Introduction

The mask system 100 may be connected to a supply of pressurizedbreathable gas to deliver therapy to the patient. The air deliverysystem 130 may include: an elbow 140 and a tube 150 as shown in FIGS.1-3.

3.2 Elbow

Elbow 140 is generally an L-shaped, hollow cylinder and may beconstructed of a generally rigid material such as polycarbonate orpolypropylene. Elbow 140 may also include one or more vent holes 160(see FIG. 3) to allow exhaust gases from the patient to expel into theatmosphere. Elbow 140 may also include a one way anti-asphyxia valve.

In a further embodiment, the elbow 140 may be the same as that disclosedin U.S. patent application Ser. No. 12/219,852 (Guney).

3.3 Tube

Tube 150 is generally a hollow, cylinder with a reinforcing member 155(see FIGS. 1 and 3) integrally molded into tube 150. The reinforcingmember 155 may include a generally helical shape so as to allow the tube150 to flex without occluding. Tube 150 may be flexible, resilient andstretchable in a longitudinal direction.

Tube 150 may be constructed of a polymer or fabric, e.g., Hytrel™. Sucha tube is disclosed in U.S. Provisional Patent Application No.61/031,407 (Henry et al), filed 26 Feb. 2008, which is incorporatedherein by reference in its entirety.

Tube 150 may connect to the elbow 140 so as to deliver breathable gas tothe patient through the patient interface 10. The tube 150 may connectto elbow 140 by any reasonable means, such as a clip, interference fit,etc.

In a further embodiment, the tube 150 may be the same as that disclosedin U.S. patent application Ser. No. 12/219,852 (Guney).

In the illustrated forms of the invention, the mask system 100 of whichthe foam interfacing portion forms a part is generally configured underthe nose of the patient. However, in other forms, the mask system 100may be a nasal or full-face mask, or an oro-nasal mask. For example, inone form, a foam-based under-the-nose configuration may be combined witha gel, silicone or rubber portion, for example a silicone mouth cushion.

While the invention has been described in connection with what arepresently considered to be the most practical and preferred embodiments,it is to be understood that the invention is not to be limited to thedisclosed embodiments, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the invention. Also, the various embodiments described abovemay be implemented in conjunction with other embodiments, e.g., aspectsof one embodiment may be combined with aspects of another embodiment torealize yet other embodiments. Further, each independent feature orcomponent of any given assembly may constitute an additional embodiment.Furthermore, each individual component of any given assembly, one ormore portions of an individual component of any given assembly, andvarious combinations of components from one or more embodiments mayinclude one or more ornamental design features. In addition, while theinvention has particular application to patients who suffer from OSA, itis to be appreciated that patients who suffer from other illnesses(e.g., congestive heart failure, diabetes, morbid obesity, stroke,bariatric surgery, etc.) can derive benefit from the above teachings.Moreover, the above teachings have applicability with patients andnon-patients alike in non-medical applications.

1. A patient interface for delivering breathable gas to a patient, thepatient interface comprising: a foam interfacing portion adapted toprovide a nasal interface to contact under and around the patient's nosein use, and the foam interfacing portion including an orifice adapted tosurround both the patient's nares in use; and a positioning andstabilizing structure to support the foam interfacing portion in anoperative position on the patient's face, wherein the positioning andstabilizing structure is structured to provide a range of rotational,axial, and/or lateral movement to the foam interfacing portion whilemaintaining a sufficient interface and resisting the application of tubedrag and/or headgear tension to the foam interfacing portion.
 2. Apatient interface according to claim 1, wherein the positioning andstabilizing structure includes a decoupling element, a frame, and/orheadgear.
 3. A patient interface according to claim 2, wherein the foaminterfacing portion is provided to an exterior surface of the decouplingelement.
 4. A patient interface according to claim 2, wherein the foaminterfacing portion is wrapped around the frame and the decouplingelement.
 5. A patient interface according to claim 4, wherein the foaminterfacing portion is secured in its wrapped position by one or moreconnectors.
 6. A patient interface according to claim 5, wherein theconnectors includes a male connector and a female connector.
 7. Apatient interface according to claim 6, wherein the foam interfacingportion includes the male connector and the frame and/or decouplingelement includes the female connector.
 8. A patient interface accordingto claim 5, wherein the connectors includes a hook and loop arrangement.9. A patient interface according to claim 5, wherein the connectorsincludes a press stud arrangement.
 10. A patient interface according toclaim 5, wherein the connectors includes a hook and loop material.
 11. Apatient interface according to claim 5, wherein the connectors includesa clip arrangement.
 12. A patient interface according to claim 2,wherein the decoupling element is formed from silicone.
 13. A patientinterface according to claim 2, wherein the foam interfacing portion issecured in position using existing structure on the decoupling element,frame, and/or headgear.
 14. A patient interface according to claim 2,wherein the orifice is structured to align with an orifice provided tothe frame and/or decoupling element.
 15. A patient interface accordingto claim 1, wherein the orifice of the foam interfacing portion isD-shaped.
 16. A patient interface according to claim 1, wherein theorifice of the foam interfacing portion includes a width of about 15-50mm.
 17. A patient interface according to claim 1, wherein the orifice ofthe foam interfacing portion includes a height of about 5-30 mm.
 18. Apatient interface according to claim 1, wherein the foam interfacingportion includes a thickness of about 0.5-50 mm.
 19. A patient interfaceaccording to claim 1, wherein the foam interfacing portion includes alength of about 10-200 mm and a width of about 10-100 mm.
 20. A patientinterface according to claim 1, wherein the foam interfacing portion isstructured to form a seal with the patient's nares.